Estrogen and thrombosis: controversies and common sense

High thrombin-activatable fibrinolysis inhibitor expression in thrombi from stroke patients in elevated estrogen states

BACKGROUND

The risk of acute ischemic stroke (AIS) associated with high estrogen states, including pregnant patients and those using oral contraceptives, has been well documented. We described the histological composition of thrombi collected in these cases.

METHODS

From a prospective tissue registry (STRIP registry) of thrombi retrieved during mechanical thrombectomy for AIS, we identified 5 patients with high estrogen states: 1 post-partum patient, 1 undergoing hormone replacement therapy and 3 consuming oral contraceptive pills. Five male control patients were randomly chosen matched by age. Immunohistochemistry for CD42b (platelets), von Willebrand factor (vWF), thrombin-activatable fibrinolysis inhibitor (TAFI), fibrinogen and plasminogen activator inhibitor-1 (PAI-1) was performed. Expression was quantified using Orbit Image Software. Student's t-test was performed as appropriate.

RESULTS

Mean TAFI content for the high estrogen state group was higher than controls (25.6 ± 11.9% versus 9.3 ± 9.0%, p = 0.043*). Mean platelet content for the high estrogen state group was lower than controls (41.7 ± 10.6% versus 61.8 ± 12.9%, p = 0.029*). No significant difference was found in vWF, fibrinogen and PAI-1 expression. Mean time to recanalize was higher in the high estrogen state group compared to the control group (57.8 ± 27.6 versus 22.6 ± 11.4 min, p = 0.0351*). The mean number of passes required was higher in the high estrogen group compared to controls 4.6 versus 1.2, p = 0.0261*).

CONCLUSIONS

TAFI expression, a powerful driver of thrombosis, was significantly higher in stroke thrombi among patients with high estrogen states compared to controls.

Thromboembolism and Oral Contraceptives During the COVID-19 Pandemic: A Disproportionality Analysis Within the Spanish Pharmacovigilance Database

Background

Thromboembolic events (TEs) are known to be a severe complication for COVID-19. They are associated with a systemic inflammatory response syndrome with coagulation cascade activation.

Objective

The aim of this study was to determine a potential association between the COVID-19 pandemic and the increment of the risk of suspected TEs in women on systemic hormonal contraceptives (SHCs).

Patients and Methods

This study utilised a case/non-case approach in the Spanish Pharmacovigilance Database, which includes more than 290,000 cases of suspected adverse drug reactions (ADRs). The reporting odds ratio (ROR) was calculated during an initial pandemic period in 2020 compared with a pre-pandemic period in 2019 and an additional control period in 2018.

Results

While there was a decreased number of ADR notifications for any medications and for any type of ADR in patients on SHCs during the pandemic period, the TE ROR for all SHCs was higher in the 2020 pandemic period [ROR = 11.8 (5.6–24.7)] relative to the pre-pandemic period in 2019 [ROR = 6.3 (3.2–12.5)] and the additional control period in 2018 [ROR = 4.6. (2.1–9.9)]. In contrast, ROR for progestogen-only contraceptives was lower during the pandemic as compared with the two control periods.

Conclusion

The reported disproportionality of TEs in women on SHCs rose during the pandemic period. This suggests a potential interaction of the drug (SHC) with COVID-19, which led to an increased risk of TEs in women exposed to both factors. This should be taken into consideration in the context of the COVID-19 pandemic.

Estrogen and estrogen receptors in kidney diseases

Acute kidney injury (AKI) and chronic kidney disease (CKD) are posing great threats to global health within this century. Studies have suggested that estrogen and estrogen receptors (ERs) play important roles in many physiological processes in the kidney. For instance, they are crucial in maintaining mitochondrial homeostasis and modulating endothelin-1 (ET-1) system in the kidney. Estrogen takes part in the kidney repair and regeneration via its receptors. Estrogen also participates in the regulation of phosphorus homeostasis via its receptors in the proximal tubule. The ERα polymorphisms have been associated with the susceptibilities and outcomes of several renal diseases. As a consequence, the altered or dysregulated estrogen/ERs signaling pathways may contribute to a variety of kidney diseases, including various causes-induced AKI, diabetic kidney disease (DKD), lupus nephritis (LN), IgA nephropathy (IgAN), CKD complications, etc. Experimental and clinical studies have shown that targeting estrogen/ERs signaling pathways might have protective effects against certain renal disorders. However, many unsolved problems still exist in knowledge regarding the roles of estrogen and ERs in distinct kidney diseases. Further research is needed to shed light on this area and to enable the discovery of pathway-specific therapies for kidney diseases.

Estrogen and thrombosis: A bench to bedside review

Estrogen, in the clinical setting is used primarily for contraception and hormone replacement therapy. It has been well established that estrogen increases the risk of both arterial and venous thrombosis. While estrogen is known to induce a prothrombotic milieu through various effects on the hemostatic pathways, the exact molecular mechanism leading to those effects is not known. The most common clinical presentation of estrogen-related thrombosis is venous thromboembolism (VTE) of the deep veins of the legs or pulmonary vessels, usually within the first few months of use. Estrogen has also been associated with increased risk of "unusual site" thromboses, as well as arterial thrombosis. Women at high-risk of thrombosis need careful evaluation and counseling for contraception, pregnancy, menopausal hormonal therapy and other estrogen-related conditions or treatments in order to lower the risk of thromboses. We review the most recent evidence on management of high-estrogen states in women at high-risk of thrombosis, as well as emerging data on unique populations such as transgender women. More studies are needed to better understand the pathophysiology of hormone-related thrombosis, as well as more comprehensive techniques to stratify risks for thrombosis so as to enable tailoring of recommendations for each individual.

Impact of Severity of Illness on the Function of the Hypothalamo-pituitary-gonadal Axis in Postmenopausal Women with Acute Severe Illness: Implications for Predicting Disease Outcome

BACKGROUND

While elevated levels of estradiol were predictive of mortality in critically ill surgical and trauma patients, their ability to predict outcome in nonsurgical patients has not been studied. We aimed to study the determinants of gonadotropin levels in acutely ill postmenopausal women with nonsurgical disease and the impact of changes in the gonadal axis on the outcome of these patients.

METHODS

Thirty-five postmenopausal women admitted to medical intensive care with acute severe illness and having a Simplified Acute Physiology Score (SAPS II score) ≥30 (in-hospital mortality rate ≥ 10%) were recruited. On the 5^th day of hospitalization, fasting samples were collected at 8.00 am and tested for luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, free triiodothyronine, free thyroxine, thyrotropin, cortisol, prolactin, dehydroepiandrosterone, androstenedione, and sex hormone-binding globulin. Multiple linear regression analysis was performed to identify independent determinants if any of LH and FSH. Receiver operating characteristic (ROC) curves were drawn for different cutoffs of LH, FSH, and estradiol to diagnose mortality and prolonged hospitalization.

RESULTS

There was an independent negative association between the FSH and the SAPS II score (beta = -0.435; P = 0.014), but not with any of the other tested parameters (estradiol, prolactin, or cortisol). Among components of the SAPS II score, the total leukocyte count (TLC) was negatively associated with serum FSH (beta coefficient = -0.635, P = 0.013). None of these parameters were determinants of LH. On ROC analysis, neither estradiol nor gonadotropins were diagnostic for in-hospital mortality. However, among survivors, low estradiol was diagnostic for prolonged hospital stay (area under the curve = 0.785; P = 0.015).

CONCLUSION

FSH, but not LH, is negatively associated with the severity of illness, particularly to its inflammatory component (TLC). Low estradiol in survivors was a predictor of prolonged hospital stay.

Evaluation of activity of hypothalamo-pituitary-gonadal axis in postmenopausal women suffering from severe acute illness

Background & objectives:

Postmenopausal women constitute an ideal model for studying the extent of hypothalamo-pituitary gonadal (HPG) axis suppression in critical illness as the gonadotropins are normally high and non-cyclical in them. The objective was to assess the impact of acute severe illness in postmenopausal women on the HPG axis and the activities of the hypothalamo-pituitary-adrenal (HPA), the hypothalamo- pituitary-thyroid (HPT) axes; and levels of serum prolactin, by comparison between critically ill postmenopausal women and otherwise healthy postmenopausal women.

Methods:

Thirty five consecutive postmenopausal women older than 60 yr admitted to medical intensive care with a Simplified Acute Physiology Score II (SAPS II) more than 30 were included. On day five of their in-hospital stay, blood samples were collected for oestradiol, luteinizing hormone (LH), follicle stimulating hormone (FSH), cortisol, androstenedione, prolactin and thyroid profile. Thirty five apparently healthy postmenopausal women were selected as controls.

Results:

Levels of LH, FSH, thyrotropin, free thyroxin (fT₄) and free tri-iodothyronine (fT₃) were lower while oestradiol, cortisol and dehydroepiandrosterone were higher among patients in comparison to healthy controls. Prolactin levels were similar in patients and controls. Among sick patients both FSH and fT₄ showed a negative correlation (P<0.05) with the SAPS II score.

Interpretation & conclusions:

In critically ill postmenopausal women, paradoxically elevated oestrogen levels despite gonadotropin suppression suggests a non-ovarian origin. Prolactin remained unaltered in patients despite their illness, possibly reflecting atrophy of lactotrophs in menopause.

Cerebral Venous Sinus Thrombosis

The frequency of patients diagnosed with cerebral venous sinus thrombosis (CVST) has increased due to the expanded use of noninvasive brain imaging methods. The aim of this study was to assess the correlations between the location and extent of venous sinus impairment, clinical presentation during the acute phase, recanalization, the presence of parenchymal lesions, and clinical outcome after 3 to 4 months in patients with CVST. In a retrospective study, clinical and magnetic resonance imaging data from a cohort of 51 consecutive patients with CVST (mean age 33.1 ± 15.4 years) were collected and analyzed. Good clinical outcome after 3 to 4 months, which was assessed using the modified Rankin scale, significantly negatively correlated with a thrombosis location in the left transverse, left sigmoid, or superior sagittal sinus ( P = .022, P = .045, and P = .046, respectively) and positively correlated with recanalization ( P = .048). The clinical outcome was significantly more favorable in the females with gender-specific risk factors than in the males ( P = .029). In conclusion, successful recanalization substantially helps to achieve good clinical outcome in patients with CVST.

The sexual dimorphism associated with pulmonary hypertension corresponds to a fibrotic phenotype

Although female predominance in the development of all types of pulmonary hypertension (PH) is well established, many clinical studies have confirmed that females have better prognosis and higher survival rate than males. There is no clear explanation of why sex influences the pathogenesis and progression of PH. Using a rat angioproliferative model of PH, which closely resembles the primary pathological changes observed in humans, we evaluated the role of sex in the development and progression of PH. Female rats had a more pronounced increase in medial thickness in the small pulmonary arteries. However, the infiltration of small pulmonary arteries by inflammatory cells was found only in male rats, and this corresponded to increased myeloperoxidase activity and abundant adventitial and medial fibrosis that were not present in female rats. Although the level of right ventricle (RV) peak systolic pressure was similar in both groups, the survival rate in male rats was significantly lower. Moreover, male rats presented with a more pronounced increase in RV thickness that correlated with diffuse RV fibrosis and significantly impaired right cardiac function. The reduction in fibrosis in female rats correlated with increased expression of caveolin-1 and reduced endothelial nitric oxide synthase-derived superoxide. We conclude that, in the pathogenesis of PH, female sex is associated with greater remodeling of the pulmonary arteries but greater survival. Conversely, in males, the development of pulmonary and cardiac fibrosis leads to early and severe RV failure, and this may be an important reason for the lower survival rate among males.

Sex, stroke, and inflammation: the potential for estrogen-mediated immunoprotection in stroke

Stroke is the third leading cause of death and the primary cause of disability in the developed world. Experimental and clinical data indicate that stroke is a sexually dimorphic disease, with males demonstrating an enhanced intrinsic sensitivity to ischemic damage throughout most of their lifespan. The neuroprotective role of estrogen in the female brain is well established, however, estrogen exposure can also be deleterious, especially in older women. The mechanisms for this remain unclear. Our current understanding is based on studies examining estrogen as it relates to neuronal injury, yet cerebral ischemia also induces a robust sterile inflammatory response involving local and systemic immune cells. Despite the potent anti-inflammatory effects of estrogen, few studies have investigated the contribution of estrogen to sex differences in the inflammatory response to stroke. This review examines the potential role for estrogen-mediated immunoprotection in ischemic injury.

Life-Threatening Complications of Hormonal Contraceptives: A Case History

We present a case with the rare combination of thrombotic and hemorrhagic complications of oral contraceptives. A healthy 40-year-old woman suffered from cardiac arrest due to massive pulmonary embolism, caused by oral contraceptives and immobilization during a flight. After successful resuscitation, obstructive shock necessitated thrombolysis and thereafter heparin. Anticoagulation was complicated by internal bleeding from contraceptive related hepatic adenoma. She underwent arterial embolisation, and anticoagulation was continued. On day 18, she was discharged in a good condition. Hepatic adenomas are a potential source of internal bleeding in women using oral contraceptives requiring anticoagulation. Signs of internal bleeding in such patients should prompt immediate abdominal ultrasound examination.

[Risk of deep venous thrombosis during an air flight: prevention and counselling at the counter]

Worldwide air traffic reaches about 2.3 billion passengers per year. The increasing number of persons at thrombo-embolic risk, together with potentially severe or fatal complications of deep venous thrombosis, suggests community pharmacists can give basic preventive advice to persons identified as at risk.